The present invention relates to steel stud building wall systems and especially to apparatuses for stabilizing steed studs to prevent lateral movement and torsion in such systems.
Many industrial, and a growing number of residential, buildings are constructed with steel stud wall framing for a variety of reasons. Steel framing is fireproof, does not warp, cannot be infested, and does not rot. When a wall is built with any kind of stud, wood or steel, it is generally desirable to fix sequential studs relative to each other and each against lateral movement and torsion. In wood-stud walls, a short piece of wood blocking is typically nailed to adjacent stud pairs to stabilize them. In steel-stud walls, an elongated steel bridging member is typically inserted horizontally through pre-punched openings in a series of vertical studs to keep them aligned. Steel studs have excellent columnar strength when they are straight, but a significant portion of that strength is lost if the studs are twisted. Because steel studs are particularly vulnerable to torsion, the bridging member, which is typically channel-shaped, having a horizontal web and two vertical side flanges, is made to closely fit the openings in the vertical studs in order to maximize torque resistance. In additional to mechanical torque, metal studs can twist or bend in response to the heat of a fire when the drywall sheathing, which acts as a firebreak, is destroyed. When metal studs twist or bend, they lose their weight-bearing capacity, multiplying the damage caused directly by fire.
While channel-shaped bridging members closely received in the openings can help restrain the studs from twisting, some twisting can still occur and the studs can still shift or bend parallel to the wall. A variety of sheet metal brackets, beginning with a simple right angle, have been designed to prevent this shifting or bending. The prior art brackets are all relatively labor intensive to install and their connections are all relatively weak. Fore example, with the simple right angle bracket, the installer places the horizontal leg of the bracket on the bridging member and the vertical leg of the bracket against the web of the wall stud. Screws are inserted through both legs to attach the bracket to the bridging member and the stud. The bracket relies on the screw connections to function, and the installer must ensure that the bracket is placed correctly. Later prior art brackets have improved on this basic connection.
The prior art also includes short bridging members that, like the wood blocking members mentioned above, span only adjacent studs and have ends tailored for fastening the wall studs, but these bridging members are relatively expensive because they use additional material to form the ends, they require a large number of fasteners, and they are necessarily of fixed length, which makes them useless if the spacing between any two studs has to be varied from the norm.
The prior art also includes elongated bridging members with a series of slots that are designed for mating with the opening in the wall stud webs, but these make relatively weak connections and also have the disadvantage that they cannot accommodate any variation in the spacing between studs.
It is an object of the present invention to provide a bracket that uses less material than prior art brackets, installs faster and more easily using fewer fasteners, and forms a connection that is stronger, resisting both lateral and torsional loads better than the prior art. It is a particular object of the present invention to provide a bracket that can be installed both outside and within the channel shape of the typical bridging member. The ability to install within the channel shape is especially advantageous because bridging members are frequently installed upside down, as a u-channel instead of the more correct n-channel.